CVE-2026-102055 Juniper Networks CVE debrief

Who should care

Network administrators and security teams responsible for Juniper Networks Junos OS on MX Series and Junos OS Evolved on PTX Series platforms should assess exposure and prioritize remediation, especially if enhanced CFM mode is enabled.

Why it matters

CVE-2026-102055 is a high-severity vulnerability in Juniper Networks Junos OS and Junos OS Evolved, allowing potential arbitrary code execution or denial of service. Network administrators and security teams should prioritize verification of exposure and remediation.

• Potential for arbitrary code execution as root.
• Possible denial of service via specific CFM Message.
• Verification of exposure and remediation priority for Juniper Networks Junos OS on MX Series and Junos OS Evolved on PTX Series platforms.
• Limited information available on affected versions and remediation steps.

Technical summary

The vulnerability exists in the cfmd process of Juniper Networks Junos OS on MX Series and Junos OS Evolved on PTX Series platforms. An unauthenticated adjacent-network attacker can exploit this vulnerability by sending a specific CFM Message to a configured down-MEP with enhanced CFM mode enabled, potentially leading to arbitrary code execution as root or denial of service. Affected product deployments should be verified for exposure, and administrators should prioritize remediation, especially if enhanced CFM mode is enabled, by reviewing and applying vendor-provided patches or workarounds.

Defensive priority

Network administrators and security teams should prioritize verification of exposure and remediation, especially for Juniper Networks Junos OS on MX Series and Junos OS Evolved on PTX Series platforms with enhanced CFM mode enabled.

Recommended defensive actions

• Verify exposure of Juniper Networks Junos OS on MX Series and Junos OS Evolved on PTX Series platforms with enhanced CFM mode enabled.
• Review and apply vendor-provided patches or workarounds.
• Monitor network traffic for suspicious activity.
• Update incident response plans to include procedures for potential exploitation.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but vendor-provided information is limited. Further verification is required to determine the full scope of affected systems and remediation steps.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.